1. Field of the Invention
The present invention relates to improvements in devices for changing die elements in crimp presses or the like, particularly as a complete set of die elements for the press rather than as individual die elements.
2. Description of Related Art
In the field of fluid connectors and in particular, hose assemblies, the preferred method of attaching a metal coupling onto a flexible or resilient hose is by crimping or swaging. This process involves permanently reducing, by application of mechanical forces, the radial dimensions of the outer sleeve of the coupling assembly and sandwiching the hose between the outer sleeve and an inner support tube. This provides both a fluid and mechanical connection of the coupling onto the flexible hose. Machines that achieve the foregoing are typically called a “crimp press” or a “swage press”. As the forces required to crimp the outer collars of the hose coupling (ferrule) are very large, hydraulic actuation forces are normally used in these machines. In hydraulically actuated crimp presses a series of die shoes are disposed circumferentially about a work space where the crimping process is to occur, the die shoes are moved radially inwardly (or outwardly) by axial movement of an annular piston with ramp surfaces engaging radially outer surfaces of the die shoes. Movement of the annular piston is achieved by applied hydraulic fluid pressure. To the radial inner surfaces of the die shoes, a respective die element is releasably connected having a radially inner work engaging surface that presses against a ferrule or similar during a crimping process. Often a crimping process may take place in stages whereby progressively varying sized sets of die elements are attached to the die shoes to carry out a complete crimping process. Of course crimping different couplings and coupling sizes also requires the use of different sized and shaped die elements. The die elements may have differing radial dimensions and differing axial lengths. Generally a crimping machine will have one die element for each die shoe, however the number of die shoes can vary from machine to machine. It is, however a relatively common practice to have eight uniformly circumferentially spaced die shoes in a typical crimping press, and thus to change eight die elements each time a differing crimping effect is required can be time consuming, particularly if they are changed individually, ie one at a time.
Current existing methods of changing die elements within a crimp press generally fall into two types. A first method employs headed pins threaded into the radially outer surfaces of the die elements. A second method employs a dovetail arrangement where the dies slide through machined channels within the die shoes. In order to change a die element set with some kind of tool, most tool designs employ a magnet in combination with some sort of interlocking arrangement to “grab” the die element set (ie multiple die elements) and remove or install same into the crimp head of the crimp press. These tools require the magnet as they have not been able to attach themselves to both sides of the die elements for the following reasons. Firstly the die elements vary in length for different crimp diameters. Secondly, in a given die element set range for a given machine, the outside diameter will be constant but the inside diameter will vary. There is usually no method of attaching to the radially outer side of the die element set because it will be attached or engaged against the die shoes. Most arrangements of tools remove/install the die element set in the fully collapsed (or closed) position.
It is believed most existing systems require the die shoes to move radially inwardly to the radially inner closed or collapsed position to allow the die elements to be attached to the removal tool and thereafter the die shoes are moved outwardly to separate the die elements from the die shoes. The die shoes may thereafter be moved from the crimp head of the crimp press. Thus multiple die shoe radial movements inwardly and outwardly are required each time a set of die elements is to be changed.
To connect a new set of die elements to the die shoes, the tool carrying the die elements is positioned in the work space and the die shoes are again moved inwardly to connect with the new die elements carried by the tool. The die shoes, once the die elements are connected thereto are then moved radially outwardly to separate the die elements from the tool, and in the outer position, after the change tool has been removed and a work piece placed into the work space, the die shoes are moved inwardly to carry out a further crimping process stage. As will be apparent from the foregoing, to illustrate a die element or die element set change, four separate operations must be performed. As these machines function relatively slowly due to safety issues as well as their powerful nature, the total operation may not be much quicker than changing the die elements individually or one at a time.
The objective of the present invention is to provide a tool for changing a die element set in a crimp press or similar in a simpler, quicker and more convenient fashion.